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A198134
Decimal expansion of least x having 2*x^2+3x=4*cos(x), negated.
3
1, 5, 3, 9, 9, 9, 5, 2, 2, 7, 2, 6, 6, 8, 3, 9, 0, 8, 1, 8, 0, 5, 9, 8, 8, 5, 8, 0, 2, 0, 4, 0, 5, 4, 2, 5, 3, 5, 5, 4, 3, 3, 5, 8, 2, 9, 2, 4, 3, 1, 7, 9, 4, 9, 6, 0, 9, 4, 6, 6, 9, 4, 6, 6, 3, 8, 4, 5, 0, 1, 2, 5, 0, 3, 2, 8, 3, 5, 1, 3, 8, 9, 7, 0, 5, 5, 5, 3, 7, 9, 3, 3, 0, 0, 3, 6, 7, 1, 9
OFFSET
1,2
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
Least x: -1.5399952272668390818059885802040...
Greatest x: 0.6975345552284129937951740662521298...
MATHEMATICA
a = 2; b = 3; c = 4;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -2, 1}]
r1 = x /. FindRoot[f[x] == g[x], {x, -1.54, -1.539}, WorkingPrecision -> 110]
RealDigits[r1] (* A198134 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .79, .70}, WorkingPrecision -> 110]
RealDigits[r2] (* A198135 *)
PROG
(PARI) solve(x=-2, -1, 2*x^2+3*x-4*cos(x)) \\ Charles R Greathouse IV, Apr 15 2026
CROSSREFS
Cf. A197737.
Sequence in context: A296345 A317907 A075693 * A082454 A377226 A108245
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 22 2011
STATUS
approved